<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>CSS定位</title>
<style>
	#box1{ width:50px; height:50px; background:red; }
	#box2{ width:50px; height:50px; background:green; 
		position:relative; left:50px; top:50px; }
	#box3{ width:50px; height:50px; background:blue; }	
</style>
</head>
<body>
<div id="box1"></div>
<div id="box2"></div>
<div id="box3"></div>
</body>
</body>
</html>




